chrome.contentSettings API: Block patterns that match extension URLs for mic and video

components/content_settings/core/common/content_settings_pattern.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/content_settings/core/common/content_settings_pattern.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "components/content_settings/core/common/content_settings_pattern_parser.h"
+#include "components/crx_file/id_util.h"
 #include "net/base/url_util.h"
 #include "url/gurl.h"
 
 namespace {
 
 // The component supports only one scheme for simplicity.
 const char* non_port_non_domain_wildcard_scheme = NULL;
 
+// Hardcode this value to avoid additional dependency.
+const char kExtensionScheme[] = "chrome-extension";
+
 // Keep it consistent with enum SchemeType in content_settings_pattern.h.
 const char* const kSchemeNames[] = {
   "wildcard",
   "other",
   url::kHttpScheme,
   url::kHttpsScheme,
   url::kFileScheme,
-  "chrome-extension",
+  kExtensionScheme,
 };
 
 static_assert(arraysize(kSchemeNames) == ContentSettingsPattern::SCHEME_MAX,
               "kSchemeNames should have SCHEME_MAX elements");
 
 std::string GetDefaultPort(const std::string& scheme) {
   if (scheme == url::kHttpScheme)
     return "80";
   if (scheme == url::kHttpsScheme)
     return "443";
@@ skipping 484 matching lines @@
   : is_valid_(false) {
 }
 
 ContentSettingsPattern::ContentSettingsPattern(
     const PatternParts& parts,
     bool valid)
     : parts_(parts),
       is_valid_(valid) {
 }
 
+bool ContentSettingsPattern::MatchesExtensionUrls() const {
+  // Check if the host pattern matches an extension ID. This can happen in two
+  // cases:
+  // 1. Host pattern is a valid extension ID.
+  // 2. Host pattern has a wildcard and hostname is empty. This means the host
+  // pattern is simply "*" and not a subdomain pattern like "[*.]google.com."
+  const bool host_pattern_matches_extension_id =
+      crx_file::id_util::IdIsValid(parts_.host) ||
+      (parts_.has_domain_wildcard && parts_.host.empty());
+  return host_pattern_matches_extension_id &&
+         (parts_.is_scheme_wildcard || parts_.scheme == kExtensionScheme);
+}
+
 bool ContentSettingsPattern::Matches(
     const GURL& url) const {
   // An invalid pattern matches nothing.
   if (!is_valid_)
     return false;
 
   const GURL* local_url = &url;
   if (url.SchemeIsFileSystem() && url.inner_url()) {
     local_url = url.inner_url();
   }
@@ skipping 275 matching lines @@
   if (!parts.is_path_wildcard && other_parts.is_path_wildcard)
     return ContentSettingsPattern::PREDECESSOR;
 
   int result = parts.path.compare(other_parts.path);
   if (result == 0)
     return ContentSettingsPattern::IDENTITY;
   if (result > 0)
     return ContentSettingsPattern::DISJOINT_ORDER_PRE;
   return ContentSettingsPattern::DISJOINT_ORDER_POST;
 }